From 2dbd34373e7dacf1e40370ac71610e545de57b93 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 22 Nov 2011 17:30:32 +0000 Subject: [PATCH] ARM: LPAE: mark memory banks with start > ULONG_MAX as highmem Memory banks living outside of the 32-bit physical address space do not have a 1:1 pa <-> va mapping and therefore the __va macro may wrap. This patch ensures that such banks are marked as highmem so that the Kernel doesn't try to split them up when it sees that the wrapped virtual address overlaps the vmalloc space. Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas Acked-by: Nicolas Pitre --- arch/arm/mm/mmu.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index 1935311e17fc..b836d6b2258b 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -799,6 +799,9 @@ void __init sanity_check_meminfo(void) struct membank *bank = &meminfo.bank[j]; *bank = meminfo.bank[i]; + if (bank->start > ULONG_MAX) + highmem = 1; + #ifdef CONFIG_HIGHMEM if (__va(bank->start) >= vmalloc_min || __va(bank->start) < (void *)PAGE_OFFSET) @@ -810,7 +813,7 @@ void __init sanity_check_meminfo(void) * Split those memory banks which are partially overlapping * the vmalloc area greatly simplifying things later. */ - if (__va(bank->start) < vmalloc_min && + if (!highmem && __va(bank->start) < vmalloc_min && bank->size > vmalloc_min - __va(bank->start)) { if (meminfo.nr_banks >= NR_BANKS) { printk(KERN_CRIT "NR_BANKS too low, " @@ -830,6 +833,17 @@ void __init sanity_check_meminfo(void) #else bank->highmem = highmem; + /* + * Highmem banks not allowed with !CONFIG_HIGHMEM. + */ + if (highmem) { + printk(KERN_NOTICE "Ignoring RAM at %.8llx-%.8llx " + "(!CONFIG_HIGHMEM).\n", + (unsigned long long)bank->start, + (unsigned long long)bank->start + bank->size - 1); + continue; + } + /* * Check whether this memory bank would entirely overlap * the vmalloc area. -- 2.39.5